I'm not able to get a video working.
The video is on my PC.
Who can help me?

What are you trying?
Easiest way for me is to ul the video to youtube and use the media tab....to paste the youtube id into
You will of course need the allvideo plugin from joomlaworks

Hi William,

I tried to, but video was blocked, because the ownder doesn't want it to be copied in a frame (something like that, I don't remember the exact words).
The company sent me the video some time ago and I thought it might be the easiest way to use this copy!?
I already installed K2 and Allvideo plugin.
What to do now?

If youtube blocked the streaming there must be a reason.
You can upload the video to your server and stream it from there

Is it not possible to use the copy I've already got on my computer?

In Plugin manager > Allvideos > Basic Options > Video Parameters I read that there is (or should be) a Local Video Folder (called images/videos), where you sstore all the video files you want to stream/play from your own website.
Maybe a stupid question, but where can I find this folder???

If your site is running on localhost, then you can use the file on your computer.
If your site is live running on a webserver, you will need to upload the file to your server, then choose it in the media tab to serve it to the world

At this moment it's running on XAMPP.
Question is: where do I find this peticular folder??